I saw Captain Marvel last night, and I have to say it was rather disappointing. I love Marvel movies and have no problem with a female superhero lead. Wonder Woman was fantastic.
That said, Captain Marvel is a Mary Sue character. She's fun to watch, but ultimately she has very little of a real or compelling personality. She's way overpowered, and she knows it. Her slow discovery of her past made the movie enjoyable, and the action was great, as always. But her character left a great deal to be desired.
Marvel movies usually strike the perfect mix between action, humor, and character development. Sadly, the main character in this movie was flat, overpowered, and the "strong woman" stereotype.
Another major weakness — and warning SPOILERS — the Kree twist is not well worked out and seems abrupt and unjustified. One moment, the Kree are noble warrior heroes. The next, they're evil. That's not how good storytelling works.
I'd love to have seen two or three scenes slowly establishing why the Kree are evil, and that would have met the emotional threshold necessary for such a huge plot twist. As it stands, the movie abruptly moves from supporting one side to supporting the other, and the explanation is very much lacking.
Captain Marvel is a fun movie, but it is far too on-the-nose and it falls far short of the Marvel secret sauce and the excellent character development in Wonder Woman. I deeply wish a character as deeply intertwined in the Marvel Cinematic Universe and as pivotal to Avengers: Endgame (as Captain Marvel is) would be a deeper, more compelling figure. It cheapens the entire universe to have a Mary Sue at the center of it.